Places to Ride in Boulder and Estes Park Area

I am visting Boulder in August and plan to spend some time in Rocky Moutain Nat. Park to do some hiking. I also want to ride some of the trails in the area. What does everyone recommend? I'm an intermediate to advanced rider. Appreciate all the feedback.

temps in Boulder and Lyons about the same. Estes Park, being higher will be cooler. If it's still in the 90s down low, then hit West Mag (Magnolia area around Nederland, Sourdough, South Saint Vrain, Crosier. If you're affected by altitude a little lower and some tree shaded are Betasso/Benjamin above Boulder, Heil Ranch. Hall Ranch nice but not many trees if you're looking for shade.
South end of Boulder are Marshall Mesa, Spring Brook (has trees).
Have fun and getting a map - Latitude 40, or Sky Terrain - from a local shop is good.

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